1. Field of the Invention
The present invention is directed to methods and apparatus for folding and inserting letters into envelopes for mailing, and in particular to methods and apparatus of this type which are capable of operating "on line" with a printer or copier.
2. Description of Related Art
The flexibility and speed of present electronic printers make them ideal for use in a variety of billing and advertising "direct mail" applications.
Some "off-line" devices have been made which take electronically printed sheets (with the address printed on one side and the bill printed on the other) and fold and seal them to form envelopes as shown in FIG. 1. This yields a single sheet ready to mail output. Folding systems also exist which can nest other items into the sheet being folded.
For example, U.S. Pat. Nos. 3,265,382 and 3,416,785 disclose paper nesting on envelope apparatuses. Both patents disclose means, provided for producing a first fold of a sheet and for nesting a second folded sheet within the folded portions of the first sheet. Means are further provided to affect a second folding of the first sheet whereby the second sheet is completely enveloped within the first sheet. U.S. Pat. No. 3,242,637 is directed to a sheet folding and inserting apparatus wherein sheets and envelopes are fed in timed relation so that the sheet can be folded and inserted into the envelope. An envelope feeding mechanism includes a reciprocating rack which is cam actuated to feed an envelope at a prior time. In U.S. Pat. No. 4,031,818 an apparatus for preparing sealed envelope units with messages is disclosed and in FIG. 1 shows a folding station for folded envelope blanks. An adhesive application station is provided as shown in FIG. 1.
U.S. Pat. No. 2,346,142 to Anderson discloses an automatic pressure-sensitive adhesive tape dispenser which measures lengths of pressure-sensitive adhesive tape supplied from a reel. Rollers are provided so that one or both serve as a sealing means to press tape against a top and/or bottom of an object.
U.S. Pat. No. 4,312,169 to Golicz et al discloses a mechanism for making an envelope around an insert. First and second conveyors move the envelope past folding mechanisms and further past a suitable adhesive applicator. The machine may operate with a previously separated letter assembly and envelope assembly.
U.S. Pat. No. 3,845,698 to Scholle discloses a method for making an envelope containing a separate enclosure sheet, wherein the letter sheet and envelope may be automatically folded, separated and assembled with the detached letter inside the formed envelope. A composite sheet consisting of an envelope-enclosure unit is fed to an automatic folding and sealing machine, the enclosure is folded about itself and the line joining the enclosure to the envelope into an overlying engagement with a portion of the envelope and secured by means of glue spots. The enclosure is then separated from the envelope, and the envelope is folded and sealed about the enclosure.
U.S. Pat. No. 4,530,730 to Bradley et al and U.S. Pat. No. 4,530,731 to Bradley disclose methods for making envelope assemblies with at least one separate enclosure from the same web of sheet material which is contour cut before folding and scoring. A fugitive glue is applied behind the scoreline, and the enclosure portion of the web is folded over the envelope portion. The mailing assembly is formed by scoring and folding the flaps.
None of the above-mentioned patents disclose an "on-line" system which can take electronically printed sheets, bills or advertisements, fold them and then put them into other printed sheets that have been folded to form envelopes. Additionally, none of these patents disclose methods or apparatus for forming envelopes from sheets which are the same size as the letter (or enclosure) sheets without requiring trimming of at least the edges of the letter sheet so that the letter will fit within the width of the envelope sheet. This trimming is required because the envelope is usually formed by gluing opposed edges of a once-folded sheet to each other. This method for forming the envelopes results in an envelope which has an internal space which is less than the width of the sheet used to form the envelope. Therefore, letters or other material inserted into the envelope must also have a width which is less than the width of the sheet used to form the envelope.
U.S. Pat. No. 4,900,391 to Mandel et al, the disclosure of which is herein incorporated by reference, discloses a sheet recirculating, folding and gluing system which folds documents, holds them at a wait station, and then inserts them into another sheet which is folded and glued "on-line" to form an envelope. The sheet used to form the envelope is larger than or the same size as the sheet which is folded and inserted therein (e.g., a letter). When the envelope sheet is the same size as the inserted sheets, the sides of the inserted sheet(s) must be trimmed using a slitter or the envelope sheet must be arranged with its longitudinal axis perpendicular to the longitudinal axis of the inserted sheet(s) prior to folding.
It is desirable to provide an "on-line" envelope forming and insertion system which is capable of using "same size" sheets to form the envelope and the inserts which does not require trimming or rotation of the sheets. Such a system would require less components (no slitter or rotator) and could also be made more compact since it would only have to handle sheets which were inserted short edge first (the paper handling system must be made wider for handling sheets fed long edge first). It is also desirable to provide a system which adhesively closes the ends of an envelope after all folding and inserting is completed so that the other components of the system do not become fouled with adhesive.
The disclosed apparatus may be readily operated and controlled in a conventional manner with conventional control systems. Some additional examples of control systems for various prior art copiers with document handlers, including sheet detecting switches, sensors, etc., are disclosed in U.S. Pat. Nos. 4,054,380; 4,062,061; 4,076,408; 4,078,787; 4,099,860; 4,125,325; 4,132,401; 4,144,550; 4,158,500; 4,176,945; 4,179,215; 4,229,101; 4,278,344; 4,284,270, and 4,475,156. It is well known in general, and preferable, to program and execute such control functions and logic with conventional software instructions for conventional microprocessors. This is taught by the above and other patents and various commercial copiers. Such software will of course vary depending on the particular function and the particular software system and the particular microprocessor or microcomputer system being utilized, but will be available to or readily programmable by those skilled in the applicable arts without undue experimentation from either verbal functional descriptions, such as those provided herein, or prior knowledge of those functions which are conventional, together with general knowledge in the software and computer arts. Controls may alternatively be provided utilizing various other known or suitable hardwired logic or switching systems.
All references cited in this specification, and their references, are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features, and/or technical background.